Protective mask



FIG. 1 is a top and right-side perspective view of a protect mask showing my new design;

FIG. 2 is a bottom and left-side perspective view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a front-side view thereof;

FIG. 5 is a rear-side view thereof; and,

FIG. 6 is a top-side view thereof. 

CLAIM The ornamental design for a protective mask, as shown and described. 